The malfunctioning of protein kinases (PKs) is the hallmark of numerous diseases. A large share of the oncogenes and proto-oncogenes involved in human cancers code for PKs. The enhanced activities of PKs are also implicated in many non-malignant diseases, such as benign prostate hyperplasia, familial adenomatosis, polyposis, neuro-fibromatosis, psoriasis, vascular smooth cell proliferation associated with atherosclerosis, pulmonary fibrosis, arthritis glomerulonephritis and post-surgical stenosis and restenosis. PKs are also implicated in inflammatory conditions and in the multiplication of viruses and parasites. PKs may also play a major role in the pathogenesis and development of neurodegenerative disorders.
For a general reference to PKs malfunctioning or disregulation see, for instance, Current Opinion in Chemical Biology 1999, 3, 459-465.
Phosphatidylinositol 3-kinases (PI3Ks) are a family of lipid and serine/threonine kinases that catalyze the phosphorylation of the membrane lipid phosphatidylinositol (PI) on the 3′-OH of the inositol ring to produce phosphoinositol-3-phosphate (PIP), phosphoinositol-3,4-diphosphate (PIP2) and phosphoinositol-3,4,5-triphosphate (PIP3), which act as recruitment sites for various intracellular signalling proteins, which in turn form signalling complexes to relay extracellular signals to the cytoplasmic face of the plasma membrane. These 3′-phosphoinositide subtypes function as second messengers in intracellular signal transduction pathways (see e.g. Trends Biochem. Sci 22 87, 267-72 (1997) by Vanhaesebroeck et al.; Chem. Rev. 101 (8), 2365-80 (2001) by Leslie et al (2001); Annu. Rev. Cell. Dev. Boil. 17, 615-75 (2001) by Katso et al; and Cell. Mol. Life. Sci. 59 (5), 761-79 (2002) by Toker et al).
Multiple PI3K isoforms categorized by their catalytic subunits, their regulation by corresponding regulatory subunits, expression patterns and signalling specific funtions (p110α, β, δ, γ) perform this enzymatic reaction (Exp. Cell. Res. 25 (1), 239-54 (1999) by Vanhaesebroeck and Katso et al., 2001, above).
The closely related isoforms p110α and β are ubiquitously expressed, while δ and γ are more specifically expressed in the haematopoietic cell system, smooth muscle cells, myocytes and endothelial cells (see e.g. Trends Biochem. Sci. 22 (7), 267-72 (1997) by Vanhaesebroeck et al). Their expression might also be regulated in an inducible manner depending on the cellular, tissue type and stimuli as well as disease context. Inductibility of protein expression includes synthesis of protein as well as protein stabilization that is in part regulated by association with regulatory subunits.
Eight mammalian PI3Ks have been identified so far, including four class I PI3Ks. Class Ia includes PI3Kα, PI3Kβ and PI3Kδ. All of the class Ia enzymes are heterodimeric complexes comprising a catalytic subunit (p100α, p110β or p110δ) associated with an SH2 domain containing p85 adapter subunit. Class Ia PI3Ks are activated through tyrosine kinase signalling and are involved in cell proliferation and survival. PI3Kα and PI3Kβ have also been implicated in tumorigenesis in a variety of human cancers. Thus, pharmacological inhibitors of PI3Kα and PI3Kβ are useful for treating various types of cancer.
PI3Kγ, the only member of the Class Ib PI3Ks, consists of a catalytic subunit p110γ, which is associated with a p110 regulatory subunit. PI3Kγ is regulated by G protein coupled receptors (GPCRs) via association with 3′ subunits of heterotrimeric G proteins. PI3Kγ is expressed primarily in hematopoietic cells and cardiomyocytes and is involved in inflammation and mast cell function. Thus, pharmacological inhibitors of PI3Kγ are useful for treating a variety of inflammatory diseases, allergies and cardiovascular diseases.
These observations show that deregulation of phosphoinositol-3-kinase and the upstream and downstream components of this signalling pathway is one of the most common deregulations associated with human cancers and proliferative diseases (see e.g. Parsons et al., Nature 436:792 (2005); Hennessey et al., Nature Rev. Drug Discovery 4: 988-1004 (2005).
The mammalian target of rapamycin (mTOR) also known as FK506 binding protein 12-rapamycin associated protein 1 (FRAP1) is a protein which in humans is encoded by the FRAP1 gene. mTOR is a serine/threonine protein kinase that regulates cell growth, cell proliferation, cell motility, cell survival, protein synthesis, and transcription. The inhibition of mTORs are believed to be useful for treating various diseases/conditions, such as cancer (for example, as described in Easton et al. (2006). “mTOR and cancer therapy”. Oncogene 25 (48): 6436-46).
The listing or discussion of an apparently prior-published document in this specification should not necessarily be taken as an acknowledgement that the document is part of the state of the art or is common general knowledge.
US patent application US 2009/0163489 and international patent application WO 2009/085230 both disclose various molecules containing a 6,5-fused bicyclic core, which may be useful as inhibitors of PI3 kinase (PI3-K). However, these documents do not relate to 6,5-bicyclic compounds that are substituted on the 6-membered ring with at least two substituents, an aromatic group and a morpholinyl group, or compounds that are substituted on the 5-membered ring with an alkyl or heterocycloalkyl moiety (linked via a carbon atom).
International patent applications WO 2007/127175 and WO 2006/046040 both disclose various thienopyrimidines and furopyrimidines, of potential use as PI3-K inhibitors. However, these documents do not disclose or suggest any other 6,5-fused bicyclic compounds.
International patent application WO 2004/092177 discloses various triazolopyrazines for use in modulating the A2a adenosine receptor signalling pathways. International patent applications WO 2006/027346, WO 2007/032936, WO 2005/042537, WO 2007/088168, WO 2008/131050, WO 03/000693, WO 2004/005290 and WO 2004/005291 and US patent application US 2006/0084650 (and international patent application WO 2006/044687) disclose various bicyclic compounds that may be useful for treating diseases/disorders such as cancer, pain, neurodegenerative disorders and/or that may be useful as kinase inhibitors. However, these documents do not relate to such bicycles that are directly substituted with both an aromatic group and a morpholinyl group.
International patent applications WO 2008/113469 and WO 2009/007029 disclose various compounds including bicyclic compounds, for use in treating diseases such as haematological diseases. However, these documents do not relate to bicycles that are substituted with a morpholinyl group.
Journal article Chorvat et al., J. Med. Chem. 1999, 42, 833 discloses various bicyclic compounds that may possess biological activity. However, there is no disclosure of 6,5-fused bicycles in which the 6-membered ring is directly substituted with an aromatic group.
International patent application WO 2005/035532 discloses various triazolopyrazinones that may be useful in the treatment of asthma or another glycogen synthase kinase mediated condition. However, this document only discloses 6,5-bicyclic compounds in which there is a carbonyl group attached to the 5-membered ring.
US patent applications US 2007/078136 and US 2008/045536 (and equivalent application WO 2007/038314) as well as international patent application WO 2008/116064 both disclose various compounds, including bicycles, which may be useful in the treatment of inflammatory and immune diseases. However, these documents do not predominantly relate to 6,5-fused bicyclic compounds that are substituted with both an aromatic group and a morpholinyl group.
French patent application FR 26661163 discloses various 6,5-fused bicycles, but does not specifically relate to 6,5-bicycles bearing an aromatic group and a morpholinyl group on the 6-membered ring. Nor does this document relate to kinase inhibitors.
International patent application WO 2010/119264 discloses various imidazopyrazines for use as kinase inhibitors, which imidazopyrazines may be substituted with an aromatic group and a morpholinyl group. However, this document only relates to imidazopyrazines.